Moulding equipment with cores for concrete casting machines

ABSTRACT

In connection with casting concrete blocks with cavities, e.g. foundation blocks, perforated blocks and elements with cavities, a moulding equipment including a bottom part ( 4 ) with casting cells with pendant core members ( 8 ) bolted on corresponding to the shape of the concrete block, and a top part ( 14 ) which have pressing plates ( 20 ) projecting downwards on support rods ( 18 ) and substantially corresponding to the shape of the casting cells, and so that the pressing plates ( 20 ) by stripping the items by vertical displacement of the bottom part ( 4 ) are passed down through the casting cells ( 6 ). By the invention is indicated a bottom part ( 4 ) that include means in the form of core members ( 8 ) bolted on, forming the defined cavities in the finished block/element. The core members ( 8 ) may either be releasably bolted onto the top plate ( 10 ) of the bottom part, or, alternatively, be suspended from a yoke ( 12 ) which is releasably fastened to the mould frame, and between the mould frame and the yoke there may be a vibration dampening shim. Core members ( 8 ) may furthermore be bolted on with a vibration dampening or compact shim ( 2 ).

BACKGROUND OF THE INVENTION

The present invention concerns concreting machines of the kind typicallyused for making cast items with cavities or corings in the shape ofconcrete blocks for erecting walls and elements, including a cellularbottom part with cells opening upwards as well as downwards which definethe desired basic shape of the individual blocks and elements, and wherethe bottom part includes at least one core member placed in respectivecells where the said cavities/corings in the mould are desired to bedisposed, and a corresponding top part which have pressing pistonsprojecting downwards from an upper holding plate and formed with lowerpressing plates that fit down into respective underlying cells in thebottom part and are thereby usable for downwards ejection of the castitems from the cells, and where the bottom part includes means ensuringthat the core members keep their position in the bottom part.

The equipment is used in the way that the bottom part is placed on acasting board placed on a vibrating table with the top part in elevatedposition above the bottom part. A concrete supply car is guided alongthe upper side of the bottom part in the space below the top part forbringing concrete into the casting cells for filling up the latter withconcrete. After finishing the filling, the supply car is pulled out, andthe top part is lowered until the said pressing plates hit down on theconcrete surfaces in the respective casting cells. Then the top part isutilised as a multi-pressure piston for consolidating the concrete massin individual casting cells, which will occur under strong vibration ofthe moulding equipment in order to liberate air from the concrete mass.Hereby the concrete items are consolidated to the desired compact blockshape and uniform thickness. Then the top part is retained in its topposition in relation to the bottom part, and the bottom part is acted onby force for being lifted up from the casting board, whereby the castitems, which by the pressure maintained from the top part cannotparticipate in this elevation, will remain standing on the casting boardduring the stripping. When the stripping has ended by upwards displacingof the bottom part to a position, in which its underside is elevated toat least the level of the pressing plates of the top part, thesemi-solid cast items can be removed from the vibrating table by pushingout therefrom after lifting the top part, after which a new castingcycle can be commenced subsequent to lowering the bottom part to thecasting board and elevating the top part to its starting position.

In connection with casting concrete blocks with cavities, e.g.foundation blocks, perforated blocks and elements with cavities, thereis used a moulding equipment including a bottom part with casting cellswith pendant cores corresponding to the desired shape of thecavity/coring in the concrete block and a top part with pressing platespendant from support bars and substantially corresponding to the shapeof the casting cells, and so that the pressing plates by stripping theitems by vertical displacement of the bottom part are passed downthrough the casting cells.

From DE-A-19 701 590 is known a traditional moulding equipment On acasting plate, e.g. placed on a vibrating table, a mould frame issecured. The mould frame is arranged with the desired number ofpartitionings in order thereby to cast a number of elements. Afterplacing the partitionings in the mould, a number of cores are placedfrom above for providing corings in the finished elements. The cores arefastened in a core holding element which bear on and is fastened to themould frame. The casting mass, typically concrete, is then placed in themould, after which mould with casting mass are vibrated. After finishingconsolidation, stripping is performed by the mould frame with thecellular insert being elevated, whereby the cores are drawn up by meansof the core holder element, after which the cast elements remain on thecasting plate.

Traditionally, core members have been welded to a support of a coreiron, which in turn has been welded to the mould frame with the cells.Alternatively, the core members have been welded to a supporting yoke, astructure above the mould which has carried the core member by downwardsprojecting rods.

The drawback of the welded core member is that after the requiredhardening of the welded core member, welding is performed again on thesupport iron of the core member for fastening the core member in themould frame itself. By welding the already hardened core member,stresses arise in connection with the welding, and these stresses maygive rise to breakage later. Another drawback is that substitution ofthe core member when worn-out, is made difficult, since the welding isto be ground before the new core member can be welded in. Repeating thiswelding weakens the mould frame and depreciates its service life. Theproblem is particularly outspoken by core members that do not abut on orare in contact with one of the sides of the cells in the bottom part,and may thus not be fastened to the walls in the cells; in thefollowing, these core members are designated ‘centre core members’.

By the invention, a bottom part including new means for securing saidcore members to remain in their position in the bottom part. These meansmay in a first embodiment be constituted by at least one top platesupported by and releasably fastened to the bottom part, and that thecore members are fastened to the top plate, preferably by boltconnections.

The novel feature of the invention is that the core members forming partof the mould are fastened directly to the top plate, preferably bybolts. The above weldings are hereby avoided when mounting andexchanging the core members, which will imply weakening of the mouldframe.

The core members that are bolted to the top plate typically include oneor more intermediate pieces.

In cases where the top plate supports one or more centre core members,which are not in contact with the sides of a cell, the centre coremember/members are carried, according to the invention, by through-goingsupports in the top plate which in turn is carried releasably fastenedto the core members in contact with opposite cell sides and fastened inthe cell sides, preferably also by bolt connections. Where theseintegrated supports run, the pressing plates of the top part are thusnot coming into contact with the block items cast in the mould, makingthe surfaces of the item appear slightly uneven, but this has nopractical significance as these surfaces on the end product are hidden.

In connection with this design of the top plate, the pressing plates inthe top part are divided into several pieces.

If cast items of the kind already described, where all surfaces aresmooth, are wanted to be produced, the design of the bottom part mayalternatively be made so that the top plate on the centre coremember/members is fastened to a supporting yoke which is supported andflexibly attached to the bottom part The supporting yoke substitutes theintegrated centre core supports.

The difference of the core being bolted on the top plate or on the yokeis that if the core is bolted to the top plate, the pressing plates ofthe top part become divided so that they can come into contact with theconcrete between the core irons supports integrated in the top plate.If, however, the cores are carried by a yoke, the pressing feet of thetop part can be made in one piece corresponding to the top side of theproduct.

Another advantage of the invention is that the constituent core membersmay be built up from modules. These modules are hardened after themaking. The modules are bolted together into core members which form theinternal shape of the concrete block, and the core members are thenbolted into the mould frame.

Furthermore, the use of bolts implies that the core members may rapidlyand simply be exchanged in the mould frame. This may possibly occursimultaneously with the wear plates forming the external side of theconcrete block are exchanged; these wear plates are also bolted to themould frame.

By the invention is furthermore provided the possibility that the coremember, whether bolted to the top plate or to the supporting yoke, maybe flexibly bolted on by using a vibration dampening shim, which ispreferably disposed between the intermediate pieces and the coremembers.

The said vibration dampening shim has the advantage that it is ensuredthat not all vibrations from the consolidation are transmitted to thecore member support. By the slight flexibility inherent in the vibrationdampening shim, it is simultaneously also achieved that the core canoscillate (vibrate) independently of the mould frame and thereby improveconsolidation, resulting in that the surfaces of the cast items willappear more smooth. The vibration dampening shim implies that the coremembers can move slightly in relation to the mould frame, and that theycan oscillate slightly differently from the mould frame, furtherensuring that the core member/members are not subjected to quite sostrong vibration during the consolidating vibration, thus safe-guardingthe constituent core members.

As alternative to the ‘flexible’ bolting on of the core members attainedby using the vibration dampening shim, the vibration dampening shim maybe substituted by a compact spacer element, whereby the core members arerigidly connected to the mould frame.

DESCRIPTION OF THE DRAWING

The invention is then described briefly in more detail with reference tothe drawing, on which:

FIG. 1 is a perspective view of a moulding equipment, where a mould toppart is elevated above a mould bottom part, and where the core supportsare integrated in the top plate;

FIG. 2 is a perspective view of mould equipment where a mould top partis elevated above a mould bottom part, and where the core supports arebuilt up as a yoke;

FIG. 3 is a perspective view of a first embodiment of a core supportintegrated in the top plate according to the invention, bottom part notshown;

FIG. 4 is one of a second embodiment of a core support structured as ayoke according to the invention, bottom part not shown;

FIG. 5 is a combined side sectional view and side view of the embodimentshown in FIG. 3, bottom part not shown;

FIG. 6 is a combined side sectional view and side view of the embodimentshown in FIG. 4, bottom part not shown, and

FIG. 7 is a perspective view of stripped concrete blocks for theembodiment shown in FIGS. 1, 3 and 5.

On FIGS. 1 and 2 is shown moulding equipment 2 for a concreting machine.The bottom part 4 is shown lying on a casting board 28 on a not shownvibration table. The shown top part 14, cf. FIGS. 1 and 2, has a strongholding plate 16 to which is welded a number of downwards projectingsupport rods 18 that carry the pressing feet 20 bolted thereon, eachhaving a contour corresponding to the top side shape of the concreteblocks 22 to be cast. The pressing feet 20 will thus together form abottom plate broken by a pattern of slits between the pressing plates,and this pattern will correspond to the shape of the open cells 6 whichappear in the associated bottom part 4 which thus display the mentionedcasting cells 6 that are open both upwards and downwards.

The moulding equipment 2 shown in FIGS. 1 and 2 are shown with the toppart 14 elevated above the mould bottom part 4, ready for fillingcasting material (concrete). After filling concrete into the cells 6 andvibration at the vibrating table (not shown) with the pressing feet 20of the top part inserted in the cells 6 and in contact with the items22, it is actual to strip the items 22, in practice by elevating thebottom part 4 with the top part 14 retained, whereby the pressing feet20 will hold the items 22 down onto the casting board 28, as it appearsfrom FIG. 7.

FIGS. 3 and 4 are perspective views of the core member structure for thefirst embodiment of a core support integrated in the top plate 10according to the invention, and a second embodiment of a core supportwith structure as a yoke 12 according to the invention, respectively.Here, it appears that the two outermost semi-cores 9 are securely boltedtogether with the end gable 7 to the mould frame. The vibrationdampening shim 24 is seen here, providing that the intermediate cores,which consist of two semi-cores 9 bolted together, have littleflexibility in relation to the mould frame. This vibration dampeningshim 24 may alternatively be substituted with a compact shim, wherebythe core elements are entirely secured to the mould frame.

In FIGS. 5 and 6 are found a combined side and side sectional view ofthe core element structure for the first embodiment of a core supportintegrated in the top plate 10 according to the invention and a secondembodiment of a core support structured as a yoke 12 according to theinvention, respectively. These views also depict the vibration dampeningshim 24.

In FIG. 7 is illustrated a newly cast item 22 right after stripping. Atthe stripping the newly cast items 22 remain standing on the castingboard 28 when the bottom part 4 of the mould 2 is lifted. By thismovement of the bottom part 4 relative to the top part 14, the pressingpistons 18 are kept in their position in relation to the cast item 22,so that the cast item 22 is pressed out of the bottom mould part 4 andthus remain standing on the casting board 28. The pressing feet 20arranged at the underside of the top part 14 and/or the pressing pistons18 thus press the pre-cast item out of the mould. This is furtherfacilitated by the cores 8, 9 being designed with bevelling. Bysubsequently withdrawing the top part 14 with pressing pistons 18 andpressing feet 20 from the bottom part 4, the newly cast item 22 may thenbe transported out the machine on the casting board, and the bottom part4 lowered down to a new casting board 28, after which the mould 2 isready for a new casting cycle, possibly after applying release agentand/or mould oil.

List of Reference Numbers:

-   2 moulding equipment-   4 bottom part-   6 open cells-   7 end gable in cells-   8 cores-   9 semi-core-   10 top plate for cores-   12 yoke for cores-   14 top part-   16 top part holding plate-   18 pressing pistons-   20 pressing feet-   22 cast items-   24 vibration dampening shim-   26 intermediate pieces-   28 casting board

1. Moulding equipment (2) for concreting machines of the kind typicallyused for making cast items with cavities or corings in the shape ofconcrete blocks for erecting walls and elements, including a cellularbottom part (4) with cells (6) opening upwards as well as downwardswhich define the desired basic shape of the individual blocks andelements, and where the bottom part (4) includes at least one coremember (8) placed in respective cells where the said cavities/corings inthe mould are desired to be disposed, and a corresponding top part (14)which has pressing pistons (18) projecting downwards from an upperholding plate (16) and formed with lower pressing plates (20) that fitdown into respective underlying cells (6) in the bottom part (4) and arethereby usable for downwards ejection of the cast items from the cells(6), and where the bottom part (4) includes means ensuring that the coremembers (8) keep their position in the bottom part (4), characterized inthat the means ensuring that the core members (8) keep their position inthe bottom part (4) are constituted by at least one top plate (10)supported by and releasably fastened to the bottom part (4), and thatthe core members (8) are fastened to the top plate (10), preferably bybolt connections such that between the core members (8) and theintermediate pieces (26) there is a vibration dampening shim (24). 2.Moulding equipment (2) according to claim 1, characterized in thatbetween the top plate (10) and the core members (8) there are one ormore intermediate pieces (26).
 3. Moulding equipment according to claim2, characterized in that the pressing plates (20) in the top part (14)are divided into several pieces.
 4. Moulding equipment according toclaim 3, characterized in that where top plate (10) carries core members(8) not in contact with wall sections of the open cells (6), it (10) issecured and supported by a yoke (12) which is supported and releasablyfastened to the bottom part (4).
 5. Moulding equipment according toclaim 4, characterized in that the pressing plates (20) in the top part(14) are made as a single continuous piece.
 6. Moulding equipmentaccording to claim 5, characterized in that between the core members (8)and the intermediate pieces (26) there is a vibration dampening shim(24).
 7. Moulding equipment according to claim 6, characterized in thatbetween the core members (8) and the intermediate pieces (26) there is acompact shim (24).
 8. Moulding equipment according to claim 1, whereinthe pressing plates in the top part are divided into several pieces. 9.Moulding equipment according to claim 1, wherein the top plate carriescore members which are out of contact with wall sections of the opencells, the top plate being secured and supported by a yoke which issupported and releasably fastened to the bottom part.
 10. Mouldingequipment according to claim 9, wherein the pressing plates in the toppart are made as a single continuous piece.
 11. Moulding equipmentaccording to claim 1, wherein a vibration dampening shim is providedbetween the core members and the intermediate pieces.
 12. Mouldingequipment according to claim 1, wherein a compact shim is providedbetween the core members and the intermediate pieces.